Field of the Invention
The present invention relates to an automatic traffic control method and device, and more particularly to a device for controlling traffic at certain high risk road sites, such as busy streets, crossroads, poor visibility highway curves, steep slopes, or checkpoints.
Apart from poor road conditions, another two closely connected factors are known to be responsible for a growing number of traffic accidents. The first factor includes speeding on high risk road sites such as busy streets or crossroads, poor visibility highway curves or steep slopes. The second factor is inadequate traffic control such as poorly lit stop signs and overcrowded intersections, as well as the inability to compel every single vehicle to obey orders or traffic regulations. Many of the prior art methods and devices fail to cope with these problems.
Traffic signs are typically located at known dangerous sites to help maintain safe traffic flow. However, traffic signs are only able to remind or warn a driver of a dangerous condition. The traffic signs alone cannot prevent accidents. Likewise, while traffic lights and police are intended to control the flow of traffic by ordering drivers to slow or stop their vehicles, the number of traffic accidents keep growing.
The problem is that undisciplined or unskilled drivers, as well as those with ill intentions, do not often heed the warnings or obey the orders. To subsequently blame the guilty driver, after the fact, is not a suitable remedy.
Furthermore, under certain circumstances, even a well-intentioned and trained driver may not be in a position to slow or stop a vehicle due, for example, to vehicle brake failure. A driver may miss a poorly visible traffic sign, e.g. under heavy rain, snow, fog conditions, or even fall asleep at the wheel. In these situations, the consequences can be disastrous.
Another prior art method for controlling traffic is based upon putting speed bumps in the road at or near certain high risk sites. These bumps, though able to restrict the vehicle speed, suffer serious disadvantages. The speed bumps do not allow the imposed low speed limit to be lifted or varied irrespective of the time or day of the week, current traffic capacity, or other suitable circumstances. Unlike police, the bumps cannot discriminate between a casual violator and ambulance, police, fire brigade, or VIP's vehicle, which may be authorized to exceed speed limits when necessary. The bumps also cause excessive wear and tear to vehicles, discomfort to the passengers, higher fuel consumption and air pollution, as all bad roads do.
Thus, none of the cited prior art methods and devices is effective and reliable enough to cope with the above-mentioned traffic problems. Nor can they provide for reclaiming kinetic energy wasted by a vehicle having to decelerate in a high risk road site. What is necessary is, therefore, a virtual control method or device to ensure that every vehicle shall obey traffic laws or orders. This means that such a device should effectively operate irrespective of either material factors, e.g. conditions of the vehicle brakes, traffic sign visibility, etc., or human factors, such as the driver's personal skill, conditions or intentions. On the other hand, the device should be flexible enough to enable certain vehicles, such as those typically provided with special siren signals, to exceed the imposed speed limits. The device should be easily adjusted to adapt to changes in the dynamic condition of the road, and provide for reclaiming kinetic energy wasted by a vehicle having to decelerate in a high risk road site.
The present invention is directed to a method and device for controlling traffic in certain high risk or busy road sites. The present invention reclaims kinetic energy wasted by a braking vehicle by providing affirmative speed control tactics.